Roofing calculator



March 22, 1938. D R o 2,112,114

ROOFING CALCULATOR Filed Oct. 22, 1955 2 Sheets-Sheet l fl: B. fiaiizfiali March 22, 1938.

K. D. RAINBOLT ROOFING CALCULATOR Filed 001:1 22, 1935 2 Sheets-Sheet 2 Swarm/Km.

Patented Mar. 22, 1938 UNITED STATES PATET 1 Claim.

This invention relates to a device designed for use by an operator while standing on the ground, to accurately calculate the amount of material required in covering the roof of a building.

An important object of the invention is to provide a calculating gauge including a body portion and plumb line, the body portion having certain indicia cooperating with indicia provided in a book of charts, whereby the square feet of a.

roof may be readily determined.

With the foregoing and other objects in view which will appear as the description proceeds, the invention consists of certain novel details of con' struction and combinations of parts hereinafter more fully described and pointed out in the claim, it being understood that changes may be made in the construction and arrangement of parts without departing from the spirit of the invention as claimed.

Referring to the drawings:

Figure l is a diagrammatic view indicating the manner in which the gauge is used.

Figure 2 is an elevational view of the gauge in its active or extended position.

Figure 3 is a view showing the gauge in a closed position.

Figure 4 is a sectional view taken on line 4-4 of Figure 3.

Figure 5 is a sectional view taken on line 55 of Figure 3.

Figure 6 is a fragmental elevational view of oneof the bars, indicating the pivoted brace bars of the gauge; and

Figure '7 is a view illustrating one of the charts with which the gauge is used.

Referring to the drawings in detail, the gauge embodies a pair of bars 5 and 6 which bars are pivotally connected at "I so that the bars may swing with respect to each other, the free ends thereof being spaced apart an appreciable distance as shown by Figure 2. Connected with the bars 5 and 6, are pivoted brace bars 8, one of the bars having a notch 9 to engage the pin 10 carried by the opposite bar, so that the bars 8 will be held against breaking, in one direction, when the bars 5 and 6 havebeen moved to their extended positions.

Secured to the side face of the bar 6 is an elongated plate H which is formed with suitable graduations dividing the plate I! into spaces. These spaces are formed with letters or indicia corresponding to letters or indicia indicating the charts that cooperate with the gauge in completing a calculation. 7

The reference character 12 designates a plumb line which is secured to the bar 5 near the free end thereof, the opposite end of the plumb line 5 carrying the weight I3 so that when the gauge is in use as shown by Figure 1, and the upper edge of the bar 5 is held so that it will aline from the eye of the user, with one of the inclined edges of the roof being measured, the line 12 will be 10 moved to a position where it will fall directly over one of the letters of the elongated plate H.

One of the charts containing indicia corresponding with indicia of the plate H, is shown by Figure '7 of the drawings.

In the use of the device the gauge is held in a position as shown by Figure 1 of the drawings, and it will be seen that when the gauge is in this position, the line 12 falls over the letter H on the plate I 1. Since the width of the building including the overhang is thirty feet and the length of the building is forty feet, the chart H is considered, and the column of figures indicated by the numeral 30 at its upper end is considered. The numeral in this column 30 opposite to the number 40 in the adjacent column will give the accurate number of square feet in the roof.

While this is one example of the use of the calculator it will of course be understood that other calculations wherein a roof having a greater or less pitch than that shown, is to be measured, the calculations are made in a similar manner.

As shown, the weight I3 is connected to the line I2, by the means of the spring l4 so that when the gauge has been moved to its closed position, the weight may be moved under the bracket I5, whereupon the tension of the spring 14 will act to hold the weight in this position.

What is claimed is:

A roof measuring instrument comprising a pair of bars, means for pivotally connecting the bars, said pivot means including a member adapted to normally hold the bars in parallel spaced relation with each other, the inner surface of one of the bars being graduated, a plumb line secured to 1 the inner surface of the opposite bar and adapted to align with graduations on the inner surface of the first mentioned bar according to the angle at which the device is held while using the instrument, and means for holding the bars in their 50 extended positions.

KATHERINE D. RAINBOLT. 

